Alterations In Mice Research Articles

Analysis of Elevated Levels of Nandrolone Decanoate Induced Cytochrome- P450 Alterations in Mice.

Frequent recreational use of Anabolic Androgenic Steroids (AAS) is an instance of substance abuse which mimics the status of a natural hormone and upon prolonged exposure may lead to adverse drug reactions. These adverse drug reactions proceed in a manner so as to alter the normal metabolism of an enzyme mediated pathway such as the Cytochrome P450 (CYP) family of enzymes. The present study was conducted to investigate the impact of overuse of Nandrolone Decanoate (ND), an AAS, upon CYP enzyme activity and a CYP gene, belonging to CYP1 family. The study was carried out using normal and ND treated male albino mice. Genetic analysis was conducted using normalized and treated cDNA and reverse transcriptase polymerase chain reaction based assays. For enzyme assay, 0.1ml of 25 mg ND was administered to the animals twice a week for a period of 90 days. Genetic analysis was carried out with the same dose but administered for a period of 360 days. CYP enzyme activity increased significantly (p<0.01) in the ND treated group of animals compared to that in the normal group. However, no noticeable alteration was observed at the molecular level. From the present study it could be inferred that, at elevated doses, ND has the potential to alter hepatic CYP enzyme activity without any modification in the CYP gene. This could be due to a possible adaptive response of the living system to such drugs.

Carcinogenic response and other histopathological alterations in mice exposed to cigarette smoke for varying time periods after birth.

In spite of the outstanding role of tobacco smoking in human carcinogenesis, it is difficult to reproduce its effects in experimental animals. Based on the knowledge that a variety of mechanisms account for a higher susceptibility to carcinogens early in life, we have developed a murine model in which mainstream cigarette smoke becomes convincingly carcinogenic. The standard model involves exposure to smoke for 4 months, starting after birth, followed by an additional 3-4 months in filtered air. We evaluated herein the time- and dose-dependent response, at 7.5 months of life, of Swiss H mice that had been exposed to smoke for either 1, 2 or 4 months after birth. A one-month exposure, corresponding to a period of intense alveolarization, was sufficient to induce most inflammatory, degenerative and preneoplastic pulmonary lesions, including emphysema and alveolar epithelial hyperplasia, blood vessel proliferation and hemangiomas, reflecting an early proangiogenic role of smoking, and microadenomas bearing ki-67-positive proliferating cells as well as urinary bladder epithelial hyperplasia. Two months of exposure were needed to induce pulmonary adenomas and urinary bladder papillomas in males only, which highlights a protective role of estrogens in urinary bladder carcinogenesis. Four months, which in humans would correspond to the postnatal period, puberty, adolescence and early adulthood, were needed to induce other lesions, including tubular epithelial hyperplasia of kidney, bronchial epithelial hyperplasia and especially pulmonary malignant tumors. These findings highlight the concept that preneoplastic and neoplastic lesions occurring in adulthood can be induced by exposure to smoke early in life.

Protective effects of stigmasterol against ketamine-induced psychotic symptoms: Possible behavioral, biochemical and histopathological changes in mice.

Stigmasterol, a naturally occurring phytoestrogen has been reported to possess many pharmacological activities. The aim of the present study was to screen the effect of stigmasterol against ketamine-induced mice model of psychosis. The behavioural studies included an assessment of locomotor activity, stereotypic behaviours, immobility duration, step down latency and effects on catalepsy. Biochemical estimations involved the estimations of GABA, dopamine, GSH, MDA, TNF-α, total protein content and AChE activity. Histopathological changes and effect on androgenic parameters were also evaluated. Stigmasterol treated animals showed significant decrease in locomotor activity, stereotypic behaviours, immobility duration and increased step down latency. Biochemical estimations revealed increased GABA, GSH levels and decreased dopamine, MDA, TNF-α levels and AChE activity. These findings were confirmed by histopathological changes in the cortex part of the brain. Further, stigmasterol was not found to cause catalepsy and any adverse effect on the reproductive system. This study concluded that stigmasterol could ameliorate ketamine-induced behavioral, biochemical and histopathological alterations in mice showing its potential effects in the management of psychotic symptoms.

Inhibitory effect of bee venom against potassium bromate causing genetic toxicity and biochemical alterations in mice

Background/aim Bee venom (BV) therapy is a highly effective treatment, capable of improving one’s health. The present study attempts to assess the effect of BV on the toxicity of oral administration of potassium bromate (KBrO3) which has been widely used in food and cosmetic industries. Materials and methods Sixty adult male mice were gavaged with KBrO3 at two doses (100 and 200 mg/kg body weight) for 10 days. Afterwards, BV at a dose of 120 μg/kg body weight was injected subcutaneously three times per week for two successive weeks. The genetic study was performed using chromosomal aberration and micronucleus formation in the bone marrow, DNA fragmentation in liver cells and by sperm analysis. In addition, serum biochemical markers such as catalase and malondialdehyde, kidney, and liver functions were assessed. Results The results have shown that KBrO3 caused DNA damage that represented the increase in the frequencies of chromosome abnormalities, micronuclei formation, percentage of DNA fragmentation, and sperm morphological abnormalities. Meanwhile, the results showed that KBrO3 exhibited severe toxicity for antioxidant activities for liver and kidney functions. Conversely, BV significantly decreased the frequencies of DNA damage in all aforementioned parameters induced by KBrO3. In addition, it improved the antioxidant activities and the function of the liver and kidneys. Conclusion BV has a potent ameliorating effect against the KBrO3 hazard impacts in animal tissues especially at higher doses. This observation indicated that BV could be a potential therapeutic agent in the treatment of KBrO3 risk.

Protective Effects of Morin Hydrate on Acute Stress-Induced Behavioral and Biochemical Alterations in Mice.

Introduction:As stress affects the brain both physiologically and chemically, researchers try to find novel anti-stress compounds with beneficial therapeutic effects. In this regard, the effect of stress and its modulation by Morin hydrate was studied using different acute models in mice.Methods:The models employed were anoxic tolerance, swimming endurance, and acute restraint test. Morin hydrate or the vehicle was administered 30 minutes prior to each stress exposure while in the acute restraint test; the animals were pretreated for 7 days with Morin hydrate, vehicle, imipramine, or diazepam before stress exposure. The measured parameters were the onset of convulsion and immobility time in the anoxic tolerance and swimming endurance test, respectively, while in the acute restraint test, the animals were assessed for stress-induced anxiety using the elevated plus maze and depression using the forced swim test. Thereafter blood was withdrawn from the retro-orbital plexus and plasma separated, the brain was also isolated, homogenized, centrifuged, and the supernatant was obtained for biochemical estimation.Results:Morin hydrate (5, 10, 20 mg/kg) produced a significant reduction in immobility time in the swimming endurance test, while significantly increased the anoxic stress tolerance time. Acute restraint stress caused a significant decrease in reduced glutathione levels (which was reversed by Morin hydrate) and increased the level of malondialdehyde, a thiobarbituric acid reactive substance which is an index of oxidative stress and nitrite. These effects were attenuated by Morin hydrate. Also, pretreatment with Morin hydrate attenuates acute restraint stress-associated anxiety and depression, reversed the hyperglycemia evoked by the stressful exposure and normalized serum cholesterol levels.Conclusion:These findings suggest that Morin hydrate exhibits anti-stress effects and may be useful in the relief of stress.

Triplications of human chromosome 21 orthologous regions in mice result in expansion of megakaryocyte-erythroid progenitors and reduction of granulocyte-macrophage progenitors.

Individuals with Down syndrome (DS) frequently have hematopoietic abnormalities, including transient myeloproliferative disorder and acute megakaryoblastic leukemia which are often accompanied by acquired GATA1 mutations that produce a truncated protein, GATA1s. The mouse has been used for modeling DS based on the syntenic conservation between human chromosome 21 (Hsa21) and three regions in the mouse genome located on mouse chromosome 10 (Mmu10), Mmu16 and Mmu17. To assess the impact of the dosage increase of Hsa21 gene orthologs on the hematopoietic system, we characterized the related phenotype in the Dp(10)1Yey/+;Dp(16)1Yey/+;Dp(17)1Yey/+ model which carries duplications spanning the entire Hsa21 orthologous regions on Mmu10, Mmu16 and Mmu17, and the Dp(10)1Yey/+;Dp(16)1Yey/+;Dp(17)1Yey/+;Gata1Yeym2 model which carries a Gata1s mutation we engineered. Both models exhibited anemia, macrocytosis, and myeloproliferative disorder. Similar to human DS, the megakaryocyte-erythrocyte progenitors (MEPs) and granulocyte-monocyte progenitors (GMPs) were significantly increased and reduced, respectively, in both models. The subsequent identification of all the aforementioned phenotypes in the Dp(16)1Yey/+ model suggests that the causative dosage sensitive gene(s) are in the Hsa21 orthologous region on Mmu16. Therefore, we reveal here for the first time that the human trisomy 21-associated major segmental chromosomal alterations in mice can lead to expanded MEP and reduced GMP populations, mimicking the dynamics of these myeloid progenitors in DS. These models will provide the critical systems for unraveling the molecular and cellular mechanism of DS-associated myeloproliferative disorder, and particularly for determining how human trisomy 21 leads to expansion of MEPs as well as how such an alteration leads to myeloproliferative disorder.

Dihydrocapsiate supplementation prevented high-fat diet–induced adiposity, hepatic steatosis, glucose intolerance, and gut morphological alterations in mice

Despite the lipolytic and thermogenic properties of capsaicin, its putative use as a weight-lowering dietary supplement has been limited because of the burning sensation caused by capsaicin when it comes in contact with mucous membranes. A potential alternative to capsaicin are the capsinoids, nonpungent capsaicin analogs that exhibit effects similar to capsaicin. Whereas the antiobesity properties of capsinoids have been reported, the effectiveness of FDA-approved synthetic dihydrocapsiate has not yet been investigated. In the present study, we hypothesized that dihydrocapsiate might ameliorate high-fat diet (HFD)–induced metabolic disorders in a manner similar to capsaicin and therefore can be its nonpungent alternative. To test this hypothesis, HFD-fed mice were orally administered dihydrocapsiate (2 and 10mg/kg body weight) for 12weeks. Dihydrocapsiate modestly reduced the HFD-induced weight gain and significantly prevented the associated hyperglyceridemia and hyperinsulinemia while improving glucose tolerance. Histological and gene expression analysis showed that dihydrocapsiate significantly prevented the lipid accumulation in white adipose tissue and brown adipose tissue via targeting genes involved in energy expenditure and mitochondrial biogenesis, respectively. Dihydrocapsiate corrected hepatic triglyceride concentrations and normalized expression of genes regulating hepatic lipid and glucose metabolism. Moreover, dihydrocapsiate administration significantly improved gut morphology and altered gut microbial composition, resulting in reduced host energy availability. Collectively, these results indicate that dihydrocapsiate administration improved glucose tolerance, prevented adiposity and hepatic steatosis, as well as improved HFD-induced gut alterations, positing dihydrocapsiate as a potential food ingredient for the dietary management of HFD-induced metabolic alterations.

Extensively re-organized systemic lymph nodes provide a feasible environment for self-reactivity in lupus-prone NZB × NZW F1 mice.

Lymphadenopathy is a frequently observed symptom in systemic lupus erythematosus, although the immunological role of lymph nodes (LNs) in systemic autoimmunity remains largely unknown. Here, we performed comprehensive and systematic analyses of LNs in lupus-prone NZB × NZW F1 (BWF1) mice, demonstrating extensive tissue re-organization of the systemic LNs with follicular expansion, hyper germinal center (GC) formation, atrophy of the paracortical T-cell area and expansion of the medulla in aged BWF1 mice bearing glomerulonephritis. The proportion of B cells was significantly increased in these reactive LNs but not in the spleen, and lymphocyte subsets involved in antibody production, i.e. GC B cells, follicular helper T cells and plasma cells, were elevated. Draining LNs of the affected organs, such as the renal and cervical nodes, showed enhanced tissue re-organization and accumulation of effector lymphocytes, suggesting the presence of a positive feedback loop of regional responses. LN cells isolated from disease-bearing animals produced anti-DNA antibody, indicating activation of autoreactive lymphocytes in situ. The substantial development of disease and LN alterations in mice that received a splenectomy at a young age points to the importance of other secondary lymphoid organs, most likely LNs, for the progression of autoimmune responses independent of the spleen. Taken together, our findings highlight the value of taking LN alterations and activities into consideration for understanding the pathogenesis of systemic autoimmunity.

Co-supplementation of isomalto-oligosaccharides potentiates metabolic health benefits of polyphenol-rich cranberry extract in high fat diet-fed mice via enhanced gut butyrate production.

Cranberries are a rich source of polyphenolic antioxidants. Purified sugars or artificial sweeteners are being added to cranberry-based food products to mask tartness. Refined sugar and artificial sweeteners intake modulate gut microbiota and result in metabolic complications. We evaluated effects of isomalto-oligosaccharides (IMOs; sweet tasting non-digestible oligosaccharides) with cranberry extract (CRX) on high fat diet (HFD)-induced metabolic alterations in mice. Male Swiss albino mice were fed normal chow or HFD (58% fat kcal), and were administered either CRX (200mg/kg) alone or in combination with IMOs (1g/kg). Cecal short-chain fatty acids, abundances of selected (1) butyrate producing, (2) metabolically beneficial, and (3) selective lipopolysaccharides producing gram negative gut bacteria were studied. Further, gut-related histological, biochemical, genomic changes along with circulating pro-/anti-inflammatory markers and systemic obesity-associated metabolic changes were studied. Co-supplementation of CRX and IMOs significantly improved cecal SCFAs, especially butyrate levels, selected butyrate-producing bacteria (clostridial cluster XIVa bacteria) and butyrate kinase expression in HFD-fed mice. The combination also significantly improved gut beneficial bacterial abundance, gut histology and related changes (colon mucin production, gut permeability) as compared to individual agents. It also prevented HFD-induced systemic and tissue inflammation, glucose intolerance and systemic obesity-associated metabolic changes in adipose tissue and liver. The combination of CRX and IMOs appeared more effective in the prevention of HFD-induced gut derangements. Combination of CRX and IMOs could be advantageous for normalization of metabolic alterations seen in diet-induced obesity via beneficial modulation of gastrointestinal health.

Cardiopreventive effects of camel milk against carbon tetrachloride induced oxidative stress, biochemical and histological alterations in mice

The present study was designed to examine the preventive effects of camel milk (CM) against the toxic effects of acute exposure to carbon tetrachloride (CCl4) on the heart tissue of mice. Administration of a single dose of CCl4 caused cardio toxicity as monitored by an increase in lipid peroxidation (thiobarbituric acid reactive substances), protein carbonyl level and antioxidant markers (superoxide dismutase, catalase, glutathione peroxidase, glutathione and vitamin C) in the heart tissue. Moreover, CCl4 caused a distinguished rise of plasma aspartate aminotransferase, lactate dehydrogenase, troponin I, and creatine kinase activities. Furthermore, CM ameliorated biochemical and histological parameters as compared to CCl4-treated group. Overall, this study indicates that CM is efficient in inhibiting oxidative stress induced by CCl4 and suggests that the administration of this milk may be helpful in the prevention of cardio-toxicity complications.

SODIUM TANSHINONE IIA SULFONATE ATTENUATES LONG‐TERM BEHAVIORAL ALTERATIONS IN MICE INJECTED WITH LIPOPOLYSACCHARIDE VIA INHIBITION OF NLRP3 INFLAMMASOME ACTIVATION

RespirologyVolume 22, Issue S3 p. 129-129 APSR Poster Abstracts SODIUM TANSHINONE IIA SULFONATE ATTENUATES LONG-TERM BEHAVIORAL ALTERATIONS IN MICE INJECTED WITH LIPOPOLYSACCHARIDE VIA INHIBITION OF NLRP3 INFLAMMASOME ACTIVATION First published: 23 November 2017 https://doi.org/10.1111/resp.13207_120Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume22, IssueS3Supplement: 22nd Congress of the Asian Pacific Society of Respirology, International Convention Centre, Sydney, Australia, 23–26 November 2017November 2017Pages 129-129 RelatedInformation

Comparative effects of meso-2,3- dimercaptosuccinic acid, monensin, and salinomycin on cadmium-induced brain dysfunction in cadmium-intoxicated mice.

Cadmium (Cd) is a risk factor for neurodegenerative diseases. The purpose of this study was to compare the effects of meso-2,3-dimercaptosuccinic acid (DMSA) and the polyether ionophorous antibiotics monensin and salinomycin on Cd-induced neurodegenerative alterations in mice. The results show that subacute intoxication of mice with Cd (II) acetate (20 mg/kg body weight (BW) for 14 days) caused a significant accumulation of cadmium (Cd) in the brain. Treatment of Cd-exposed mice with DMSA (20 mg/kg BW for 14 days) significantly increased the Cd concentration in the brains compared to those of the Cd-treated group. However, administration of monensin (20 mg/kg BW for 14 days) or salinomycin (20 mg/kg BW for 14 days) significantly reduced the Cd concentration in the brains of Cd-treated mice compared to the toxic control group. Histopathological analysis of brain tissues from the Cd-treated mice revealed that Cd induced neuronal necrosis, characterized by many shrunken, darkly stained pyknotic neurons with prominent perineuronal spaces. Whereas monensin and salinomycin significantly reduced the adverse effects of Cd on brain morphology of Cd-treated mice, DMSA did not. Monensin slightly increased the copper and iron endogenous levels in the brains of Cd-exposed mice compared to those of the untreated mice. Salinomycin did not affect the concentrations of biometal ions in the brain of Cd-exposed mice compared to untreated controls. The results demonstrated salinomycin to be a better potential chelating agent for treatment of Cd-induced brain injury compared to DMSA and monensin.

Myocardial metabolic alterations in mice with diet-induced atherosclerosis: linking sulfur amino acid and lipid metabolism

Atherosclerosis is a leading cause of cardiovascular disease (CVD), but the effect of diet on the atherosclerotic heart’s metabolism is unclear. We used an integrated metabolomics and lipidomics approach to evaluate metabolic perturbations in heart and serum from mice fed an atherogenic diet (AD) for 8, 16, and 25 weeks. Nuclear magnetic resonance (NMR)-based metabolomics revealed significant changes in sulfur amino acid (SAA) and lipid metabolism in heart from AD mice compared with heart from normal diet mice. Higher SAA levels in AD mice were quantitatively verified using liquid chromatography-mass spectrometry (LC/MS). Lipidomic profiling revealed that fatty acid and triglyceride (TG) levels in the AD group were altered depending on the degree of unsaturation. Additionally, levels of SCD1, SREBP-1, and PPARγ were reduced in AD mice after 25 weeks, while levels of reactive oxygen species were elevated. The results suggest that a long-term AD leads to SAA metabolism dysregulation and increased oxidative stress in the heart, causing SCD1 activity suppression and accumulation of toxic TGs with a low degree of unsaturation. These findings demonstrate that the SAA metabolic pathway is a promising therapeutic target for CVD treatment and that metabolomics can be used to investigate the metabolic signature of atherosclerosis.

Correction to: Effects of Beta-Adrenergic Blockade on Diabetes-Induced Neurobehavioral Alterations in Mice

Correction to: Effects of Beta-Adrenergic Blockade on Diabetes-Induced Neurobehavioral Alterations in Mice

Statin therapy causes gut dysbiosis in mice through a PXR-dependent mechanism

BackgroundStatins are a class of therapeutics used to regulate serum cholesterol and reduce the risk of heart disease. Although statins are highly effective in removing cholesterol from the blood, their consumption has been linked to potential adverse effects in some individuals. The most common events associated with statin intolerance are myopathy and increased risk of developing type 2 diabetes mellitus. However, the pathological mechanism through which statins cause these adverse effects is not well understood.ResultsUsing a murine model, we describe for the first time profound changes in the microbial composition of the gut following statin treatment. This remodelling affected the diversity and metabolic profile of the gut microbiota and was associated with reduced production of butyrate. Statins altered both the size and composition of the bile acid pool in the intestine, tentatively explaining the observed gut dysbiosis. As also observed in patients, statin-treated mice trended towards increased fasting blood glucose levels and weight gain compared to controls. Statin treatment affected the hepatic expression of genes involved in lipid and glucose metabolism. Using gene knockout mice, we demonstrated that the observed effects were mediated through pregnane X receptor (PXR).ConclusionThis study demonstrates that statin therapy drives a profound remodelling of the gut microbiota, hepatic gene deregulation and metabolic alterations in mice through a PXR-dependent mechanism. Since the demonstrated importance of the intestinal microbial community in host health, this work provides new perspectives to help prevent the statin-associated unintended metabolic effects.

Effects of Beta-Adrenergic Blockade on Diabetes-Induced Neurobehavioral Alterations in Mice

Neurobehavioral activities were estimated in three groups of male albino mice using the open field, elevated plus maze, light/dark board, and hole-board tests. The control group included intact animals, while alloxan-induced diabetes was evoked in the other two groups (single i.p. injection of 120 mg/kg alloxan). In the third group, a nonspecific beta-adrenoreceptor antagonist, propranolol, was i.p. injected (40 mg/kg) before the induction of diabetes. In diabetic mice, all neurobehavioral indices tested in the four above-mentioned tests were significantly (P< 0.05) smaller than those in the control group. The frequencies of rearings and grooming episodes in the open field, number of entries into the open arms and time spent in these arms in the elevated plus maze test, and number of head dips in the hole-board test demonstrated the most intense drops (more than twofold). Pretreatment with propranolol provided significant (P < 0.05) normalization of all neurobehavioral indices in diabetic mice; such normalization with respect to the locomotion intensity, frequency of grooming, time spent in the open arms, and both indices in the light/dark board was nearly complete. Thus, diabetes in the animal model used is accompanied by the development of the state of abnormally high anxiety. The activity of the betaadrenergic system is noticeably involved in the formation of this state; pharmacological blocking of beta-adrenoreceptors provides significant anxiolytic effects.

Noninvasive assessment of cutaneous alterations in mice exposed to whole body gamma irradiation using optical imaging techniques.

We report the results of a study carried out to investigate the potential of optical techniques such as optical coherence tomography, Mueller matrix spectroscopy, and cross-polarization imaging for noninvasive monitoring of the ionizing radiation exposure-induced alterations in cutaneous tissue of mice. Radiation dose-dependent changes were observed in tissue microvasculature and tissue optical parameters like retardance and depolarization as early as 1h post radiation exposure. Results suggest that these optical techniques may allow early detection of radiation dose-dependent alterations which could help in screening of population exposed to radiation.

Isomalto-oligosaccharides, a prebiotic, functionally augment green tea effects against high fat diet-induced metabolic alterations via preventing gut dysbacteriosis in mice

High fat diet (HFD)-induced alterations in gut microbiota and resultant ‘leaky gut’ phenomenon promotes metabolic endotoxemia, ectopic fat deposition, and low-grade systemic inflammation. Here we evaluated the effects of a combination of green tea extract (GTE) with isomalto-oligosaccharide (IMOs) on HFD-induced alterations in mice. Male Swiss albino mice were fed with HFD (58% fat kcal) for 12 weeks. Systemic adiposity, gut derangement parameters and V3-V4 region based 16S rRNA metagenomic sequencing, ectopic fat deposition, liver metabolome analysis, systemic and tissue inflammation, and energy homeostasis markers along with gene expression analysis in multiple tissues were done in mice supplemented with GTE, IMOs or their combination. The combination of GTE and IMOs effectively prevented HFD-induced adiposity and lipid accumulation in liver and muscle while normalizing fasting blood glucose, insulin, glucagon, and leptin levels. Co-administration of GTE with IMOs effectively modulated liver metabolome associated with lipid metabolism. It also prevented leaky gut phenotype and HFD-induced increase in circulating lipopolysaccharides and pro-inflammatory cytokines (e.g. resistin, TNF-α, and IL-1β) and reduction in anti-inflammatory cytokines (e.g. adiponectin and IL-6). Gene expression analysis across multiple tissues further supported these functional outcomes. Most importantly, this combination improved beneficial gut microbiota (Lactobacillus sp., Bifidobacteria, Akkermansia muciniphila, Roseburia spp.) abundances, restored Firmicutes/Bacteriodetes and improved Prevotella/Bacteroides proportions. In particular, a combination of these two agents has shown improved beneficial effects on multiple parameters studied. Data presented herein suggests that strategically chosen food components might be highly effective in the prevention of HFD-induced alterations and may further be developed as functional foods.

Neonatal Immune Challenge with Lipopolysaccharide Triggers Long-lasting Sex- and Age-related Behavioral and Immune/Neurotrophic Alterations in Mice: Relevance to Autism Spectrum Disorders.

Early-life challenges, particularly infections and stress, are related to neuropsychiatric disorders such as autism and schizophrenia. Here, we conducted a wide range of behavioral tests in periadolescent (postnatal day (PN) 35) and adult (PN70) Swiss mice neonatally challenged with LPS on PN5 and -7, to unveil behavioral alterations triggered by LPS exposure. Immune and neurotrophic (brain-derived neurotrophic factor-BDNF) alterations were determined in the prefrontal cortex (PFC), hippocampus (HC), and hypothalamus (HT). Since the incidence and clinical manifestations of neurodevelopmental disorders present significant sex-related differences, we sought to distinctly evaluate male and female mice. While on PN35, LPS-challenged male mice presented depressive, anxiety-like, repetitive behavior, and working memory deficits; on PN70, only depressive- and anxiety-like behaviors were observed. Conversely, females presented prepulse inhibition (PPI) deficits in both ages studied. Behavioral changes in periadolescence and adulthood were accompanied, in both sexes, by increased levels of interleukin (IL-4) (PFC, HC, and HT) and decreased levels of IL-6 (PFC, HC, and HT). BDNF levels increased in both sexes on PN70. LPS-challenged male mice presented, in both ages evaluated, increased HC myeloperoxidase activity (MPO); while when adult increased levels of interferon gamma (IFNγ), nitrite and decreased parvalbumin were observed. Alterations in innate immunity and parvalbumin were the main LPS-induced remarks between males and females in our study. We concluded that neonatal LPS challenge triggers sex-specific behavioral and neurochemical alterations that resemble autism spectrum disorder, constituting in a relevant model for the mechanistic investigation of sex bias associated with the development of this disorder.

Bifidobacterium CECT 7765 modulates early stress-induced immune, neuroendocrine and behavioral alterations in mice

Emerging evidence suggests that there is a window of opportunity within the early developmental period, when microbiota-based interventions could play a major role in modulating the gut-brain axis and, thereby, in preventing mood disorders. This study aims at evaluating the effects and mode of action of Bifidobacterium pseudocatenulatum CECT 7765 in a murine model of chronic stress induced by maternal separation (MS). C57Bl/6J male breast-fed pups were divided into four groups, which were subjected or not to MS and supplemented with placebo or B. pseudocatenulatum CECT7765 until postnatal period (P) 21 and followed-up until P41. Behavioral tests were performed and neuroendocrine parameters were analyzed including corticosterone, cytokine/chemokine concentrations and neurotransmitters. Microbiota was also analyzed in stools by 16S rRNA gene sequencing. B. pseudocatenulatum CECT 7765 administration attenuated some aspects of the excessive MS-induced stress response of the hypothalamic–pituitary–adrenal (HPA) axis, particularly corticosterone production at baseline and in response to subsequent acute stress in adulthood. B. pseudocatenulatum CECT 7765 also down-regulated MS-induced intestinal inflammation (reducing interferon gamma [IFN-γ]) and intestinal hypercatecholaminergic activity (reducing dopamine [DA] and adrenaline [A] concentrations) at P21. These effects have a long-term impact on the central nervous system (CNS) of adult mice since MS mice fed B. pseudocatenulatum CECT 7765 showed lower anxiety levels than placebo-fed MS mice, as well as normal neurotransmitter levels in the hypothalamus. The anti-inflammatory effect of B. pseudocatenulatum CECT 7765 seemed to be related to an improvement in glucocorticoid sensitivity in mesenteric lymph node immunocompetent cells at P21. The administration of B. pseudocatenulatum CECT 7765 to MS animals also reversed intestinal dysbiosis affecting the proportions of ten Operational Taxonomic Units (OTUs) at P21, which could partly explain the restoration of immune, neuroendocrine and behavioral alterations caused by stress in early and later life. In summary, we show that B. pseudocatenulatum CECT 7765 is able to beneficially modulate the consequences of chronic stress on the HPA response produced by MS during infancy with long-lasting effects in adulthood, via modulation of the intestinal neurotransmitter and cytokine network with short and long-term consequences in brain biochemistry and behavior.